The annual Perseid meteor shower is expected to put on a good show this week for those willing to get up in the wee hours of the morning and wait patiently for the shooting stars.

In North America, the best time to watch will be between midnight to 5 a.m. on Wednesday, Aug. 12, but late Tuesday night and also Wednesday night

The Perseids are always reliable, and sometimes rather spectacular. The only things that puts a damper on the August show are bad weather or bright moonlight. Unfortunately this week, as the Perseids reach their peak Tuesday and Wednesday nights, the moon will be high in the sky, outshining the fainter meteors.

The Perseids are bits of debris from Comet Swift-Tuttle, which has laid down several streams of debris, each in a slightly different location, over the centuries as it orbits the sun. Every August, Earth passes through these debris streams, which spread out over time.

The Perseids appear to emanate from the constellation Perseus, which rises high in the sky around midnight and is nearly overhead by dawn. Like most meteor showers, the hours between midnight and daybreak are typically the best time to watch, because that's when the side of Earth you are on is rotating into the direction of Earth's travels through space, so meteors are "scooped up" by the atmosphere at higher rates, much like a car's windshield ends the lives of more bugs than does the rear bumper.

Astronomers expect up to 200 meteors per hour in short bursts of up to 15 minutes or so. But many of the fainter meteors will simply not be visible due to moonlight, and rates will go down even more for those in urban areas. More likely a typical observer under reasonably dark skies might hope to see a meteor every couple minutes when the bursts come, and fewer during lulls.

Viewing tips

The best location is far from city and suburban lights. Ideally, find a structure, mountain or tree to block the moon. Then scan as much of the sky as possible. The meteors can appear anywhere, heading in any direction. If you trace their paths backward, they'll all point to the constellation Perseus.

People in locations where any chill might occur should dress warmer than they think necessary to allow for prolonged viewing.

Seasoned skywatchers advise using a blanket or lounge chair for comfort, so you can lie back and look up for long periods. Allow at least 15 minutes for your eyes to fully adjust to the darkness. Then expect meteors to be sporadic: You might see two in a row, or several minutes could go by between shooting stars.

Avid meteor watchers might want to try scanning the northeastern horizon from 9 p.m. to 11 p.m. local time (your local time, wherever you are) for Perseids that graze the horizon.

"Earthgrazers are meteors that approach from the horizon and skim the atmosphere overhead like a stone skipping across the surface of a pond," Cooke explained. "They are long, slow and colorful – among the most beautiful of meteors." He notes that an hour of watching may net only a few of these at most, but seeing even one can make the whole night worthwhile.

Map illustrating the annual Perseid meteor shower. The night sky will sparkle with "falling stars" on Tuesday and Wednesday as Earth passes through a trail of dusty debris from the Swift-Tuttle Comet, say scientists.